STMicroelectronics has introduced its IIS3DWB vibration sensor, supported by the STEVAL-STWINKT1 multi-sensor evaluation kit, that accelerates development of condition-monitoring systems that boost productivity by inferring equipment maintenance needs.


The IIS3DWB is a 3-axis MEMS1 accelerometer optimized for industrial vibration sensing. The STEVAL-STWINKT1 simplifies prototyping and testing by integrating the IIS3DWB with additional sensors, an ultra-low-power microcontroller and algorithms for vibration processing, Bluetooth® wireless module, and USB connection. Housed in a plastic enclosure with a battery, the kit is ready to begin application development and presents a convenient reference design. High-speed data-logger and cloud-dashboard utilities are included to help collect, analyze, and visualize the results.


The IIS3DWB 3-axis ultra-wide-bandwidth MEMS accelerometer detects vibrations that are prime indicators of a machine’s service requirements. The device, which is covered under ST’s 10-year availability assurance for industrial products, is optimized for vibration monitoring. The frequency response is tailored to be fully flat and with low noise up to 6kHz and then with a sharp cutoff and high attenuation to remove frequency-aliasing concerns and to detect machine-related faults with accuracy and consistency. Low power consumption maximizes the operating lifetime of independently powered sensor nodes.


Key features of the IIS3DWB include:


  • Accelerometer with wide and flat frequency response over 3-axis saves external signal conditioning and complexity needed by competing sensors
  • Digital plug-and-play capability, integrating signal conditioning, analog-to-digital converter (ADC), filtering, and bandwidth equalization on-chip
  • Low noise: 75µg/√Hz in 3-axis mode or 60µg/√Hz in single-axis mode selectable on the fly
  • -40°C to 105°C operating-temperature range
  • 1.1mA operating current at full performance in all three axes


About the STEVAL-STWINKT1 evaluation kit

The STEVAL-STWINKT1 evaluation kit integrates multiple miniature sensors on-board in addition to the IIS3DWB. There is also a Bluetooth® Low Energy (BLE) radio for connecting to an edge device or directly to the Internet. The many on-board features let solution integrators bypass labor-intensive sensor integration to focus on their application and accelerate time to market and offer advanced software features like high-speed data logging for the benefits of new field of exploration like machine learning and AI.


Features of the STEVAL-STWINKT1 include:


  • Industrial sensors: inertial sensors, temperature, pressure, and humidity sensors, and digital and wide-bandwidth analog microphones
  • Ultra-low-power Arm® Cortex®-M4 MCU (STM32L4R9ZI) running at 120MHz with FPU, 2048 kbytes Flash, and optimized power management
  • On-board footprint for STSAFE-100 secure element IC for secure connection and authentication
  • Wireless BLE4.2 on-board and wired RS485 and USB OTG connectivity
  • Preprocessing algorithms for vibration analysis: RMS moving average and programmable FFT (overlapping, averaging, windowing)
  • High-speed data logging with real-time storage on SD-CARD and streaming via USB of data from multiple (22) sensors at their maximum resolution (ODR)
  • Companion cloud application and dashboard
  • Optional Wi-Fi expansion board (STEVAL-STWINWFV1), and STMod+ cellular expansion board from the P-L496G-CELL02 kit